使用 axios 访问在 localhost 上运行的 api 时，React Native 应用程序 GET 请求导致网络错误

Question

I'm working on an Android App that's running on an Android Emulator and it's supposed to use Axios to get data from the API that's running on my localhost:3333, the problem is that when it sends the GET request, I get a Network Error as if it can't reach anything by using the baseURL "http://localhost:3333".

I know that because it's a VM, I am supposed to use adb reverse tcp:3333 tcp:3333 to connect it's ports to the host machine to keep using "localhost";

I've already tried using the Android Studio IP "http://10.0.2.2:3333" without the adb reverse;

I've already tried using my local ip as the baseURL;

But the problem continues...

Instead of posting snippets, I'm sharing the projects, as they're very simple: APP https://github.com/March0514s/react-native react-native run-android

API https://github.com/March0514s/backend yarn dev

Obs.: I'm not sure if it's necessary to reproduce the error, but send the following POST after the server is running: curl -X POST -H "Content-Type: application/json" -d '{"title": "project", "name": "your name"} http://localhost:3333/projects

Thanks in advance

Answer 1

The problem was being caused by the back-end that was configured to use the port 3333 that was being used for something else, and that lead me to the weird behavior of being capable of getting the response by http://localhost:3333 but not from http://127.0.0.1:3333 on the host machine. Using another port fixed that problem and the techniques used for loopback on the VM worked as they should. Thanks anyway for at least reading my problem, it's always good to have a community to rely on when those weird stuff happens...